Bok takeoff soldering help

[Darth Father]

Guys, I'm working on finishing my bok. I cannot for the life of me get the takeoff line to attach to the tower. Solder takes just fine to the line itself. I finish up and go back to check it and no dice. I end up with this nice ring of solder on my line when I pull it out of the column with none left behind.

I clean the surface like crazy and flux it. I've even tried to score the surface around the opening thinking that it would give it something to hold on to. However, this is my first time soldering something that wasn't a pipe to a fitting. Is there a trick to it that I'm missing? I've looked through a ton of builds tonight and haven't come away with a reason for my failure. Going crazy here in the cold.

Darth

[Twinrivers]

It's all about heat control and a tight fit. Remember that when joining two different thicknesses your heat will need to be concentrated on the heavier material. Hope this helps. I know nothing about a bok except that they make a good neutral or so I'm told. Can you post a picture??

[YHB]

Every thing twin rivers said +

The column is not getting hot enough.

Keep the flame on the column and let the heat spread to take off line, when the solder melts every thing will work just fine.

If you are using slant plates and have already soldered them in position then be prepared for them to move, perhaps keep them in place with some jubilee clips and when the solder melts give them an extras dab of new solder.

I find it a lot less frustrating, to solder the slant plates and the take off line at the same time.

[Darth Father]

Thank you for your replies. According to both of you, I've been doing this all wrong . I've been focusing my heat on the line. Solder sticking to the line is logical now.

So doing fittings, I focus my heat where I want the solder to go, like the coupling. When doing a flat surface, where should my flame be? I'm using the Home Depot on sale propane torch.

@YHB

I'm using a reducer coupling as my collection cup, so no plates. I'll snap a pic when I head back outside.

[skow69]

Put the flame on the flat surface 1 to 2 inches away from the joint. Let the heat "wick" over to the joint so the metal melts the solder. Never melt the solder with flame.

[Hound Dog]

Just what everyone else said about indirect heating. I would add that I cut a coupling fitting down, flared out one end of it to form a little flange and then slid it over my takeoff tube. I then dry fitted it on and tapped it to fit to the column before soldering. This is only a tiny flange fitting but it gives a good amount of surface to wick solder into for a very solid connection besides just tube intersecting the sidewall of the column. Kind of doubled everything up at the narrow joint.

[myles]

I'm using a reducer coupling as my collection cup, so no plates. I'll snap a pic when I head back outside.

Excelent choice. I like Alex's designs but the slant plate is not the one I would build myself.

Soldering is a cappilary action affair. The solder flows TOWARDS the heat source. If you have been heating the tube that might explain your problem. Heat the column wall and let the heat travel into the tube. Soldering always works better if the heat and the solder are applied from opposite sides of the bit being soldered.

Difficult in this situation but try heat on the outside of the column and solder applied from the inside. You always need to think carefuly about the sequence of soldering opperations.

Your other option is a BIG flame torch. I use 19mm and bigger burners on tank fed torches for soldering big copper. Even when using 55% silver solder for brazzing coolant connectors into condensers, the massive heat source ensures good solder flow.

Your column is a big heat sink, you need to get both sides of the joint up to temperature for the solder to flow.

[dan]

Darth - Here is a little video I made to show how to solder small parts to a large copper column I hope this helps.... http://youtu.be/wdWvWTxVswg?list=UUurKp ... aat-Yr97eQ" onclick="window.open(this.href);return false;" rel="nofollow
- Dan

[humbledore]

Dan I am not planning on of building a 4" any time soon, but what kind of torch are you using in the video?

[Darth Father]

Thanks for the advice guys. I love this site. Can't wait to get home and do some work. I'm stuck at the inlaws right now.


@Dan

Great video. Very helpful. Same question as above. That looks like a badass torch.

[Twinrivers]

Hands down the best torch money can buy is a turbo torch. They are sold at plumbing supply stores and require an acetylene B tank.

[dan]

Hey Guys, The torch I use is a Bernzomatic TS4000 Trigger Start Torch. It works with both propane as well as Mapp gas. When using Mapp gas (which is all I use) the flame temp is much hotter. I hope that helps... Mapp Gas is methylacetylene-propadiene propane which is safer and easier to use than acetylene.
-Dan

[Darth Father]

Dan, does this look like a match?

http://m.homedepot.com/p/Bernzomatic-TS ... 203368730/

If so, I will purchase tomorrow on my way home.

Darth

[skow69]

Isn't the 4000 the one that is not adjustable? That just pissed me off. Like WTF, they couldn't afford to put a 10 cent valve on it? I would have paid $5 more. I think the 99 actually burns hotter anyway. And it's damn sure handier.

[dan]

Darth-
That is the same one that I use and it is not adjustable. You just pull the trigger and it is on and ready to work. Like I said I only use Mapp gas and it works great even for 4" type "L" copper that I use for my flutes and other projects.

-Dan

[Darth Father]

Well, as I age, I'm slowly learning that things are easy if you have the right tools for the job. Went and bought a MAPP torch. Job took seconds to complete. That thing is HOT. The problem was definitely not enough heat, just like you all pointed out. If you don't have a MAPP torch yet, get one.

I went ahead and took some advice from above and used a 1/4 slip coupling to create a small lip for extra support on my takeoff line.

Love this site. Thank you guys for all the help so far.

Darth